A method for suppressing the ripple current of a capacitor in a power conversion device has been proposed in the prior art (see, for example, PTL 1). Specifically, the prior art described in PTL 1 discloses the following technology.
More specifically, ripple current in a capacitor is reduced by setting the phase difference in a PWM command signal between a first inverter section and a second inverter section to 180°, and carrying out first two-phase modulation for controlling switching such that both inverter sections have a duty ratio of 0% in the smallest phase (see paragraphs [0044] to [0061] of PTL 1).
More specifically, ripple current in a capacitor is reduced by setting the phase difference in a PWM command signal between a first inverter section and a second inverter section to 180°, and carrying out second two-phase modulation for controlling switching such that both inverter sections have a duty ratio of 100% in the largest phase (see paragraphs [0062] to [0078] of PTL 1).